NBRC MOCK TMC EXAM REVIEW
QUESTIONS WITH COMPLETE
ANSWERS
Which of the following is the most appropriate recommendation?
A. Increase the liter flow to 4 L/min
B. Maintain the current O2 level
C. Institute noninvasive positive pressure ventilation (NPPV)
D. Place on a NRB mask at 12 L/min - ANSWER-B. Maintain the current O2 level
The physician has ordered O2 to be set up on a patient who has a spontaneous tidal
volume of 500 mL and an inspiratory time of 1 second. Which of the following O2
delivery devices will deliver a flow that meets or exceeds this patient's inspiratory flow?
A. 35% air-entrainment mask at 6 L/min
B. 60% aerosol mask at 12 L/min
C. NRB mask at 15 L/min
D. Simple O2 mask at 10 L/min - ANSWER-500 mL = 0.5 L
0.5/1 = 0.5 L/s (change L/s to ?/min by multiplying by 60
0.5 L x 60= 30 L/min
Select the device that delivers a flow of at least 30L/min
A. 35% air-entrainment mask at 6 L/min
A patient breathing 50% oxygen has a PaO2 of 248 torr. Which of the following should
the RT recommend?
A. Discontinue O2 therapy
B. Decrease the oxygen to 30%
C. Titrate oxygen to maintain an SpO2 > 93%
D. Repeat the blood gases because the PaO2 is not possible on this FiO2. - ANSWER-
C. Titrate oxygen to maintain an SpO2 > 93%
Explanation: A PaO2 of 250 torr is normal on 50% O2. Remember, to determine the
normal PaO2 on any given O2%, multiply the O2% by 5. This is an approximation. If
titrate was not a choice, then you would discontinue the oxygen.
A patient is receiving 30% oxygen via an air-entrainment mask at a flow of 5 L/min. The
total flow delivered by this device is which of the following?
A. 36 L/min
B. 45 L/min
, C. 54 L/min
D. 60 L/min - ANSWER-(*Use 21 with O2 % less than 40%)
(100- 30%)/ (30%-*21) = 70/9 = 8/1 or 8:1 ratio
8+1= 9
9x5 = 45 L/min
B. 45 L/min
Secretions tend to become thicker if the inspired air has which of the following
characteristics?
A. A relative humidity of 100% at body temperature
B. 32 mg H2O per liter of gas
C. A water vapor pressure of 47 mmHg
D. 48 mg H2O per liter of gas - ANSWER-B. 32 mg H2O per liter of gas
A patient receiving 38 mg H2O per liter of gas from a nebulizer has a humidity deficit of
which of the following?
A. 6 mg/L
B. 9 mg/L
C. 12 mg/L
D. 18 mg/L - ANSWER-44-38= 6
A. 6 mg/L
After connecting a nasal cannula to the humidifier outlet, you kink the tubing and hear a
whistling noise coming from the humidifier. Which of the following most likely has
caused this?
A. The humidifier jar is cracked
B. The capillary tube in the humidifier is disconnected
C. The humidifier has no leaks
D. The top of the humidifier is not screwed on tightly - ANSWER-C. The humidifier has
no leaks
You notice that the patient's secretions have become thicker and more difficult to
suction since the ventilator humidifier was replaced with an HME. The RT should
recommend which of the following?
A. Increase inspiratory flow
B. Decrease the temperature to the HME
C. Replace with a new HME
D. Replace the HME with a conventional heated humidifier - ANSWER-D. Replace the
HME with a conventional heated humidifier
QUESTIONS WITH COMPLETE
ANSWERS
Which of the following is the most appropriate recommendation?
A. Increase the liter flow to 4 L/min
B. Maintain the current O2 level
C. Institute noninvasive positive pressure ventilation (NPPV)
D. Place on a NRB mask at 12 L/min - ANSWER-B. Maintain the current O2 level
The physician has ordered O2 to be set up on a patient who has a spontaneous tidal
volume of 500 mL and an inspiratory time of 1 second. Which of the following O2
delivery devices will deliver a flow that meets or exceeds this patient's inspiratory flow?
A. 35% air-entrainment mask at 6 L/min
B. 60% aerosol mask at 12 L/min
C. NRB mask at 15 L/min
D. Simple O2 mask at 10 L/min - ANSWER-500 mL = 0.5 L
0.5/1 = 0.5 L/s (change L/s to ?/min by multiplying by 60
0.5 L x 60= 30 L/min
Select the device that delivers a flow of at least 30L/min
A. 35% air-entrainment mask at 6 L/min
A patient breathing 50% oxygen has a PaO2 of 248 torr. Which of the following should
the RT recommend?
A. Discontinue O2 therapy
B. Decrease the oxygen to 30%
C. Titrate oxygen to maintain an SpO2 > 93%
D. Repeat the blood gases because the PaO2 is not possible on this FiO2. - ANSWER-
C. Titrate oxygen to maintain an SpO2 > 93%
Explanation: A PaO2 of 250 torr is normal on 50% O2. Remember, to determine the
normal PaO2 on any given O2%, multiply the O2% by 5. This is an approximation. If
titrate was not a choice, then you would discontinue the oxygen.
A patient is receiving 30% oxygen via an air-entrainment mask at a flow of 5 L/min. The
total flow delivered by this device is which of the following?
A. 36 L/min
B. 45 L/min
, C. 54 L/min
D. 60 L/min - ANSWER-(*Use 21 with O2 % less than 40%)
(100- 30%)/ (30%-*21) = 70/9 = 8/1 or 8:1 ratio
8+1= 9
9x5 = 45 L/min
B. 45 L/min
Secretions tend to become thicker if the inspired air has which of the following
characteristics?
A. A relative humidity of 100% at body temperature
B. 32 mg H2O per liter of gas
C. A water vapor pressure of 47 mmHg
D. 48 mg H2O per liter of gas - ANSWER-B. 32 mg H2O per liter of gas
A patient receiving 38 mg H2O per liter of gas from a nebulizer has a humidity deficit of
which of the following?
A. 6 mg/L
B. 9 mg/L
C. 12 mg/L
D. 18 mg/L - ANSWER-44-38= 6
A. 6 mg/L
After connecting a nasal cannula to the humidifier outlet, you kink the tubing and hear a
whistling noise coming from the humidifier. Which of the following most likely has
caused this?
A. The humidifier jar is cracked
B. The capillary tube in the humidifier is disconnected
C. The humidifier has no leaks
D. The top of the humidifier is not screwed on tightly - ANSWER-C. The humidifier has
no leaks
You notice that the patient's secretions have become thicker and more difficult to
suction since the ventilator humidifier was replaced with an HME. The RT should
recommend which of the following?
A. Increase inspiratory flow
B. Decrease the temperature to the HME
C. Replace with a new HME
D. Replace the HME with a conventional heated humidifier - ANSWER-D. Replace the
HME with a conventional heated humidifier
